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there's nothing wrong with "as many as", as answered already; the plural form of "pizza" is "pizzas" though (or "pizze", if you want to use the Italian) - so the correct sentence would be "I delivered as many as two hundred pizzas!"
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TaoDec 27 '11 at 13:53

"As many as two" can be used rather ironically. In its literal sense, two isn't a big number, is it?
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IreneDec 27 '11 at 14:15

The maximum means that you have a upper limit so it is not correct to use it in that context (x=<1000). I agree about the others. Generally it means more or less the number. In math we would say that x is closed in [1000-e,1000+e] interval, where e is really a small number.
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speedyGonzalesDec 27 '11 at 13:45

what if I get a as many as two? Isn't two too small for such an expression?
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spaunyDec 27 '11 at 13:47